Pen



FIG. 1 is a front perspective view of a pen, showing my new design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is an elevation view thereof from the left side, the right sidebeing a mirror image thereof;

FIG. 5 is a front elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The ornamental design for a pen, as shown.